GeO2 and SiO2 thin film preparation with CVD using ultraviolet excimer lamps

We have prepared SiO2 and GeO2 thin films from tetraethoxyorthosilicate (TE OS; Si(OC2H5)(4)) and tetraethoxyorthogermanate (TEOG: Ge(OC2H5)(4)), respe ctively, by chemical vapor deposition (CVD) assisted by high-energy photons . The photons are supplied from excimer lamps which emit incoherent light a t 308 (XeCl), 222 (KrCl), 172 (Xe-2), 146 (Kr-2) and 126 mn (Ar-2). GeO2 fi lm deposition is observed for all excimer lamps used here, but SiO2 films a re obtained at wavelengths shorter than 172 rim. This is caused by a fact t hat the bonding energy between Si and O is much higher than that between Ge and O. The deposition rate is around 8nm/min for SiO2 and 16nm/min for GeO 2 films. The film deposition rate increases with increasing the fight inten sity and with decreasing substrate temperature.